package com.example.olingo.client;

import java.io.IOException;
import java.io.InterruptedIOException;
import java.net.ConnectException;
import java.net.URI;
import java.net.UnknownHostException;
import javax.net.ssl.SSLException;
import org.apache.http.HttpEntityEnclosingRequest;
import org.apache.http.HttpRequest;
import org.apache.http.client.HttpRequestRetryHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.protocol.ExecutionContext;
import org.apache.http.protocol.HttpContext;
import org.apache.olingo.commons.api.http.HttpMethod;
import org.apache.olingo.client.core.http.DefaultHttpClientFactory;

/**
 * Shows how to install a custom exception recovery mechanism.
 * <a
 * href="http://svn.apache.org/repos/asf/httpcomponents/site/httpcomponents-client-4.2.x/tutorial/html/fundamentals.html#d5e281">More
 * information</a>.
 */
public class RequestRetryHttpClientFactory extends DefaultHttpClientFactory {

  @Override
  public DefaultHttpClient create(final HttpMethod method, final URI uri) {
    final HttpRequestRetryHandler myRetryHandler = new HttpRequestRetryHandler() {

      @Override
      public boolean retryRequest(final IOException exception, final int executionCount, final HttpContext context) {
        if (executionCount >= 5) {
          // Do not retry if over max retry count
          return false;
        }
        if (exception instanceof InterruptedIOException) {
          // Timeout
          return false;
        }
        if (exception instanceof UnknownHostException) {
          // Unknown host
          return false;
        }
        if (exception instanceof ConnectException) {
          // Connection refused
          return false;
        }
        if (exception instanceof SSLException) {
          // SSL handshake exception
          return false;
        }
        final HttpRequest request = (HttpRequest) context.getAttribute(ExecutionContext.HTTP_REQUEST);
        boolean idempotent = !(request instanceof HttpEntityEnclosingRequest);
        if (idempotent) {
          // Retry if the request is considered idempotent 
          return true;
        }
        return false;
      }

    };

    final DefaultHttpClient httpClient = super.create(method, uri);
    httpClient.setHttpRequestRetryHandler(myRetryHandler);
    return httpClient;
  }

}
